To the north of San Francisco Bay, there is San Pablo Bay – with bridges connecting the communities from across the water, as well. Check out the picture I took after our take-off from San Francisco International airport today, and the map next to it.
I turned the map of San Francisco Bay (on the right) and San Pablo Bay (on the left) sideways, so that it matches the eastward view from the airplane. The bridge in the foreground is the Carquinez Bridge, and the one further in the distance the Benicia Bridge.
